The invention relates to an x-ray diagnostic generator with an x-ray tube, a high voltage transformer and an inverter supplying the high voltage transformer; the inverter is connected to a DC voltage source and has an adjustable pulse-pause ratio.
In an x-ray diagnostic generator of this type, it is possible to significantly reduce the size and weight of the high voltage transformer in contrast to that case in which it is supplied with mains frequency, when the inverter frequency lies in the mid-frequency range, for example between one and five kilohertz. It is known to adjust the x-ray tube voltage via the pulse-pause ratio of the inverter. To this end, a filter section is provided on the high voltage side, so that the voltage at the x-ray tube which is gained by means of rectification of the output voltage of the high voltage transformer depends for its peak value on the pulse-pause ratio of the inverter.
An x-ray diagnostic generator of this type is employable both for the production of x-ray exposures given stationary x-ray tubes and stationary radiation receivers, for example, x-ray film as well as for the production of x-ray tomographs wherein the exposure unit consisting of x-ray tube and radiation receiver is moved with reference to the exposure subject. In the latter case, it is necessary to keep the dose rate constant for an exposure-automated operation. It is thereby possible to attain an optimum film blackening (or density) by regulation of the dose rate applied to an x-ray film given an exposure time determined by the selected scanning path of the exposure unit.